Acanthosis nigricans is a skin condition characterized by areas of dark, velvety discoloration in body folds and creases. The affected skin can become thickened. Most often, acanthosis nigricans affects your armpits, groin and neck. The sk...

Cold antibody hemolytic anemia (CAHA) is a rare autoimmune disorder characterized by the premature destruction of red blood cells (rbcs) by the body's natural defenses against invading organisms (antibodies). Normally, the red blood cells have a l...

Mixed cryoglobulinemia is a rare disorder characterized by the presence of cryoglobulins in the blood. Cryoglobulins are abnormal proteins that thicken and clump together at cold temperatures, usually below 98.6 degrees Fahrenheit (the average hum...

Alkaptonuria is a rare genetic metabolic disorder characterized by the accumulation of homogentisic acid in the body. Affected individuals lack enough functional levels of an enzyme required to breakdown homogentisic acid. Affected individuals may...

Sneddon syndrome is a rare progressive disorder affecting the blood vessels characterized by the association of a skin condition and neurological abnormalities. Characteristics include multiple episodes of reduced blood flow to the brain (cerebral...

Tinea versicolor is a common fungal infection of the skin. The fungus interferes with the normal pigmentation of the skin, resulting in small, discolored patches. These patches may be lighter or darker in color than the surrounding skin and most c...

Cutis marmorata telangiectatica congenita (CMTC) is a rare inherited disorder characterized by discolored patches of skin caused by widened (dilated) surface blood vessels. As a result, the skin has a purple or blue "marbled" or "fishnet" appearan...

Neurofibromatosis type 1 (NF1), also called von Recklinghausen's disease, is a rare genetic disorder characterized by the development of multiple noncancerous (benign) tumors of nerves and skin (neurofibromas) and areas of abnormally decreased or ...

Neurofibromatosis type 1 (NF1), also called von Recklinghausen's disease, is a rare genetic disorder characterized by the development of multiple noncancerous (benign) tumors of nerves and skin (neurofibromas) and areas of abnormally decreased or ...

De Sanctis-Cacchione syndrome is an extremely rare disorder characterized by the skin and eye symptoms of xeroderma pigmentosum (XP) occurring in association with neurological abnormalities, mental retardation, unusually short stature (dwarfism), ...